US20050151503A1 - Converter and inverter including converter circuit - Google Patents
Converter and inverter including converter circuit Download PDFInfo
- Publication number
- US20050151503A1 US20050151503A1 US11/034,719 US3471905A US2005151503A1 US 20050151503 A1 US20050151503 A1 US 20050151503A1 US 3471905 A US3471905 A US 3471905A US 2005151503 A1 US2005151503 A1 US 2005151503A1
- Authority
- US
- United States
- Prior art keywords
- voltage
- motor
- converter
- command
- link
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M5/00—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases
- H02M5/40—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc
- H02M5/42—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters
- H02M5/44—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac
- H02M5/453—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal
- H02M5/458—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M5/4585—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only having a rectifier with controlled elements
Definitions
- the present invention relates to a converter, to an inverter including a converter circuit and, more particularly, to the control of a dc link voltage in the converter and the inventor.
- Inverters convert an applied direct current (dc) into an alternating current (ac), and are used to, for example, drive an induction motor.
- the inverter coverts an applied dc voltage into an ac voltage by performing pulse width control, etc.
- An inverter having the following configuration is also known: a converter circuit that converts an ac voltage applied from an ac power supply into a do voltage is connected to an inverter circuit (dc link); and a dc link voltage provided by the converter circuit is used as an input of the inverter circuit.
- a capacitor is often connected on the dc link between the converter circuit and inverter circuit.
- the capacitor is known to not only smooth a dc voltage into which an ac voltage is converted but also help supply or recover energy to or from a load.
- an object of the present invention is to solve the foregoing problems underlying the related arts and to facilitate supply of energy from a voltage smoothing capacitor to a load or recovery of energy from the load without the necessity of increasing the capacitance of the capacitor.
- a voltage on a dc link is dynamically controlled in order to facilitate supply of energy stored in a capacitor or recovery of excess energy into the capacitor.
- the supply of energy from a power supply or recovery of energy into the power supply is effectively minimized.
- a control technique used to retain a dc link voltage at a predetermined value is well-known.
- a control target value of the dc link voltage is dynamically changed in order to dynamically control the dc link voltage.
- the link voltage can be controlled, in the same manner as control of acceleration or deceleration of a motor, in response to a command programmed in a numerical controller.
- the present invention can be implemented in a converter or an inverter including a converter circuit.
- the converter uses a PWM to control the voltage on a dc link.
- a PWM to control the voltage on a dc link.
- the voltage on a dc link is elevated.
- the voltage on the dc link is lowered.
- the voltage on the dc link is set to a voltage higher than a normal do link voltage when energy is supplied to the load, a larger amount of energy is stored in a capacitor, and a large amount of energy can be supplied to the load at a time.
- an amount of power supplied from a power supply is reduced, and a large amount of power can be supplied to the load with the capacity of the power supply held diminished.
- the voltage on the dc link is set to a voltage lower than a normal dc link voltage when energy is recovered from the load, a larger amount of energy can be recovered into the capacity than an amount of energy recovered normally, and a large amount of energy can be recovered from the load at a time. Consequently, a current recovered by the power supply can be reduced and a loss in energy occurring over a power line can be reduced. Moreover, if a regenerated current is supplied to a resistor, the energy consumed by the resistor will be reduced.
- the foregoing converter is interposed between an inverter circuit and an ac power supply.
- a converter or an inverter in accordance with the present invention can be adapted to a case where a motor is used as the load.
- the converter and inverter will have constituent features described below.
- the voltage on the dc link is elevated prior to acceleration of the motor, and/or the voltage on the dc link is lowered prior to deceleration of the motor.
- the converter can control the voltage on a dc link using a PWM and is used to drive a motor.
- the voltage on the dc link is elevated prior to acceleration of the motor, and lowered prior to deceleration of the motor.
- the voltage on the dc link is elevated in response to a dc link voltage elevating command described in a motor control program (for example, a numerical control program).
- a motor control program for example, a numerical control program.
- the dc link voltage elevating command is programmed to be issued a predetermined time earlier than a motor acceleration command.
- the magnitude of an input current necessary for elevating a dc link voltage can be arbitrarily set in response to a command described in the numerical control program. For example, a voltage difference by which the voltage on the dc link is elevated or a length of the elevation period is determined based on a current permitted by a power supply or a converter, and described in the numerical control program.
- the voltage on the dc link is lowered in response to a dc link voltage lowering command described in a motor control program (for example, a numerical control program).
- the dc link voltage lowering command is programmed to be issued a predetermined time earlier than a motor deceleration command.
- the magnitude of an input current necessary for lowering the voltage on the dc link can be arbitrarily set in response to a command described in the numerical control program. For example, a voltage difference by which the voltage on the dc link is lowered or a length of the lowering period is determined based on a current permitted by a power supply or a converter, and described in the numerical control program.
- the supply of energy from a voltage smoothing capacitor to a load or recovery of energy from the load can be facilitated without the necessity of increasing the capacitance of the capacitor.
- FIG. 1 is an explanatory diagram schematically showing an inverter in accordance with the present invention
- FIG. 2 shows an example of the configuration of a converter circuit in accordance with the present invention
- FIG. 3 is an explanatory diagram concerning control of a dc link voltage to be extended at the time of accelerating a motor according to the present invention
- FIG. 4 is an explanatory diagram concerning control of a do link voltage to be extended at the time of decelerating a motor according to the present invention
- FIG. 5 shows the relationship of a dc link voltage to a motor speed
- FIG. 6A and FIG. 6B are explanatory diagrams concerning the relationship of a voltage variation to a time interval established according to the present invention.
- FIG. 1 is an explanatory diagram schematically showing an inverter in accordance with the present invention.
- An inverter 10 shown in FIG. 1 comprises a converter circuit 12 that converts an ac voltage applied from an ac power supply into a dc voltage, a voltage smoothing capacitor 13 , and an inverter circuit 14 that inverts a dc voltage into an ac voltage of a predetermined frequency and applies the ac voltage to a load (a motor M).
- the converter circuit 12 controls a do link voltage.
- FIG. 2 shows an example of the configuration of the converter circuit.
- the converter circuit 12 is controlled by PWM to allow a control circuit 15 to switch the on and off states of transistors such as IGBTs.
- the technology of retaining a dc link voltage at a predetermined value using a PWM is well-known.
- a control target value of the dc link voltage is dynamically changed in order to dynamically control the do link voltage.
- the link voltage is controlled, in the same manner as acceleration or deceleration of a motor is, in response to a command programmed in a numerical controller.
- control of the converter circuit employed in the present invention will be described by taking, as an example, a case where a motor serves as a load.
- the formula (1) demonstrates that an absolute value ′′V 2 ⁇ V 1
- the present invention utilizes the fact that the energy stored in or released from the capacitor depends on the absolute value of the difference between the controlled voltage V 2 on the dc link and the initial voltage V 1 .
- the voltage V on the dc link is dynamically controlled so that a larger amount of energy will be stored in or released from the capacitor than it is when the voltage is not controlled.
- dynamic control of a dc link voltage is, similarly to control of acceleration or deceleration of a motor, performed in response to a command programmed in a numerical controller.
- the voltage on the dc link is elevated (b) from the initial voltage (a) on the dc link to the controlled voltage V 2 on the dc link (c).
- V 2 on the dc link the controlled voltage
- the voltage on the dc link elevated, supply of energy to the motor is started in order to start accelerating the motor (at a motor acceleration start time instant A in the drawing).
- the voltage on the dc link falls (d) and eventually reaches a constant voltage (e).
- the voltage on the dc link is lowered (g) from an initial voltage (f) to a voltage (h) corresponding to the controlled voltage V 2 on the dc link.
- deceleration of the motor is started and recovery of regenerated energy from the motor is started (at a motor deceleration start time instant B in the drawing).
- the voltage on the do link rises (i) owing to recovered energy.
- the dc voltage reaches a voltage (j).
- FIG. 5 shows the relationship between a programmed command and changes in a dc link voltage and a motor speed.
- reference numeral 20 denotes the motor speed
- reference numeral 22 denotes the dc link voltage.
- a command 26 for elevating the dc link voltage is written in a program before to a motor acceleration command 24 .
- the command for elevating the dc link voltage is released at a step at which the motor is accelerated to a predetermined speed ( 28 ).
- a command 32 for lowering the do link voltage is written in the program before to a motor deceleration command 30 .
- the command for lowering the dc link voltage is released at a step at which the motor is decelerated to a predetermined speed (for example, a zero speed) ( 33 ).
- a voltage variation such as an elevation voltage difference or a lowering voltage difference and/or a length of the elevation or lowering period is specified as a parameter in a program.
- FIG. 6A and FIG. 6B are graphs for explaining the relationship between a voltage variation
- either of the voltage variation ⁇ V and the time interval T may be held constant as shown in FIG. 6A and FIG. 6B , and the time interval T may be specified as a parameter according to a permissible current.
- a time interval T 1 is specified for a relatively large permissible current
- a time interval T 2 is specified for a relatively small permissible current.
- a converter in accordance with the present invention and an inverter including the converter can be adapted to a motor in which supply and recovery of power is carried out. Moreover, the converter and inverter can be adapted to a motor in which recovery of energy is not carried out but only consumption of energy is carried out.
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Inverter Devices (AREA)
- Control Of Ac Motors In General (AREA)
- Rectifiers (AREA)
Abstract
In an inverter comprising a converter circuit that converts an alternating current into a direct current and an inverter circuit that inverts the direct current into the alternating current, supply of energy from a voltage smoothing capacitor to a load or recovery of energy from the load is facilitated without the necessity of increasing the capacitance of the voltage smoothing capacitor interposed between the converter circuit and inverter circuit. In the converter circuit, before the supply of energy to the load is started, the voltage on a dc link is raised. Before collection of energy from the load is started, the voltage on the dc link is lowered.
Description
- 1. Field of the Invention
- The present invention relates to a converter, to an inverter including a converter circuit and, more particularly, to the control of a dc link voltage in the converter and the inventor.
- 2. Description of the Related Art
- Inverters convert an applied direct current (dc) into an alternating current (ac), and are used to, for example, drive an induction motor. The inverter coverts an applied dc voltage into an ac voltage by performing pulse width control, etc.
- An inverter having the following configuration is also known: a converter circuit that converts an ac voltage applied from an ac power supply into a do voltage is connected to an inverter circuit (dc link); and a dc link voltage provided by the converter circuit is used as an input of the inverter circuit.
- In the converter or the inverter including the converter circuit, a capacitor is often connected on the dc link between the converter circuit and inverter circuit. The capacitor is known to not only smooth a dc voltage into which an ac voltage is converted but also help supply or recover energy to or from a load.
- For example, assuming that a motor is driven using an inverter, when the motor is accelerated, energy stored in a voltage smoothing capacitor connected on a dc link in the inverter is supplied to the motor in order to help supply energy necessary for acceleration of the motor for a short period of time. When the motor is decelerated, energy regenerated by the motor is recovered into a voltage smoothing capacitor connected on the dc link in the inverter. This helps recover energy, which is regenerated during deceleration of the motor, for a short period of time.
- Consequently, an amount of energy supplied from a power supply is reduced, and an amount of energy returned to the power supply is reduced. Eventually, energy can be rapidly supplied from or returned to the power supply without the necessity of increasing the capacity of the power supply. Moreover, a loss in energy occurring over a power line can be reduced.
- The above operation of the voltage smoothing capacitor incorporated in the inverter is well-known.
- In the foregoing converter or inverter, it is conceivable, in order to facilitate smooth supply of energy to a load or smooth recovery of energy regenerated by the load is, for example, to increase the capacitance of the voltage smoothing capacitor.
- However, if the capacitance of the voltage smoothing capacitor is increased, the scale of the converter or inverter becomes larger.
- Accordingly, an object of the present invention is to solve the foregoing problems underlying the related arts and to facilitate supply of energy from a voltage smoothing capacitor to a load or recovery of energy from the load without the necessity of increasing the capacitance of the capacitor.
- According to the present invention, a voltage on a dc link is dynamically controlled in order to facilitate supply of energy stored in a capacitor or recovery of excess energy into the capacitor. Thus, the supply of energy from a power supply or recovery of energy into the power supply is effectively minimized.
- In a converter using pulse-width modulation (PWM), a control technique used to retain a dc link voltage at a predetermined value is well-known. According to the present invention, a control target value of the dc link voltage is dynamically changed in order to dynamically control the dc link voltage. In, for example, a numerically controlled machine tool, the link voltage can be controlled, in the same manner as control of acceleration or deceleration of a motor, in response to a command programmed in a numerical controller.
- The present invention can be implemented in a converter or an inverter including a converter circuit.
- The converter uses a PWM to control the voltage on a dc link. Herein, before supply of energy to a load is started, the voltage on a dc link is elevated. Moreover, before recovery of energy from the load is started, the voltage on the dc link is lowered.
- As the voltage on the dc link is set to a voltage higher than a normal do link voltage when energy is supplied to the load, a larger amount of energy is stored in a capacitor, and a large amount of energy can be supplied to the load at a time. Eventually, an amount of power supplied from a power supply is reduced, and a large amount of power can be supplied to the load with the capacity of the power supply held diminished.
- As the voltage on the dc link is set to a voltage lower than a normal dc link voltage when energy is recovered from the load, a larger amount of energy can be recovered into the capacity than an amount of energy recovered normally, and a large amount of energy can be recovered from the load at a time. Consequently, a current recovered by the power supply can be reduced and a loss in energy occurring over a power line can be reduced. Moreover, if a regenerated current is supplied to a resistor, the energy consumed by the resistor will be reduced.
- Moreover, when the present invention is implemented in an inverter, the foregoing converter is interposed between an inverter circuit and an ac power supply.
- A converter or an inverter in accordance with the present invention can be adapted to a case where a motor is used as the load. In order to adapt the converter and inverter to the motor serving as a load, the converter and inverter will have constituent features described below.
- When a converter capable of controlling the voltage on a dc link using a PWM is used to drive a motor, the voltage on the dc link is elevated prior to acceleration of the motor, and/or the voltage on the dc link is lowered prior to deceleration of the motor.
- When the present invention is implemented in a converter, the converter can control the voltage on a dc link using a PWM and is used to drive a motor. The voltage on the dc link is elevated prior to acceleration of the motor, and lowered prior to deceleration of the motor.
- For elevation of the voltage on a dc link, the voltage on the dc link is elevated in response to a dc link voltage elevating command described in a motor control program (for example, a numerical control program). The dc link voltage elevating command is programmed to be issued a predetermined time earlier than a motor acceleration command.
- The magnitude of an input current necessary for elevating a dc link voltage can be arbitrarily set in response to a command described in the numerical control program. For example, a voltage difference by which the voltage on the dc link is elevated or a length of the elevation period is determined based on a current permitted by a power supply or a converter, and described in the numerical control program.
- For lowering of the voltage on a dc link, the voltage on the dc link is lowered in response to a dc link voltage lowering command described in a motor control program (for example, a numerical control program). The dc link voltage lowering command is programmed to be issued a predetermined time earlier than a motor deceleration command.
- The magnitude of an input current necessary for lowering the voltage on the dc link can be arbitrarily set in response to a command described in the numerical control program. For example, a voltage difference by which the voltage on the dc link is lowered or a length of the lowering period is determined based on a current permitted by a power supply or a converter, and described in the numerical control program.
- In a converter in accordance with the present invention or an inverter including the converter, the supply of energy from a voltage smoothing capacitor to a load or recovery of energy from the load can be facilitated without the necessity of increasing the capacitance of the capacitor.
- An inverter in accordance with the present invention will be described in conjunction with drawings below.
-
FIG. 1 is an explanatory diagram schematically showing an inverter in accordance with the present invention; -
FIG. 2 shows an example of the configuration of a converter circuit in accordance with the present invention; -
FIG. 3 is an explanatory diagram concerning control of a dc link voltage to be extended at the time of accelerating a motor according to the present invention; -
FIG. 4 is an explanatory diagram concerning control of a do link voltage to be extended at the time of decelerating a motor according to the present invention; -
FIG. 5 shows the relationship of a dc link voltage to a motor speed; and -
FIG. 6A andFIG. 6B are explanatory diagrams concerning the relationship of a voltage variation to a time interval established according to the present invention. -
FIG. 1 is an explanatory diagram schematically showing an inverter in accordance with the present invention. Aninverter 10 shown inFIG. 1 comprises aconverter circuit 12 that converts an ac voltage applied from an ac power supply into a dc voltage, avoltage smoothing capacitor 13, and aninverter circuit 14 that inverts a dc voltage into an ac voltage of a predetermined frequency and applies the ac voltage to a load (a motor M). - In the
inverter 10 of the present invention, theconverter circuit 12 controls a do link voltage.FIG. 2 shows an example of the configuration of the converter circuit. Theconverter circuit 12 is controlled by PWM to allow acontrol circuit 15 to switch the on and off states of transistors such as IGBTs. The technology of retaining a dc link voltage at a predetermined value using a PWM is well-known. A control target value of the dc link voltage is dynamically changed in order to dynamically control the do link voltage. For example, in a numerically controlled machine tool, the link voltage is controlled, in the same manner as acceleration or deceleration of a motor is, in response to a command programmed in a numerical controller. - Next, control of the converter circuit employed in the present invention will be described by taking, as an example, a case where a motor serves as a load.
- The
voltage smoothing capacitor 13 is disposed on the dc link of the converter circuit to the inverter circuit. Energy is stored in or released from the capacitor. The energy stored in or released from the capacitor depends on a change in the voltage on the dc link and is expressed as follows:
Energy in the capacitor=(V 2 2 −V 1 2)/2C (1)
where V1 denotes an initial voltage on the do link, and V2 denotes a controlled voltage on the dc link. - The formula (1) demonstrates that an absolute value ″V2−V1| of a difference between the controlled voltage V2 on the dc link and the initial voltage V1 should be increased in order to store or release a larger amount of energy in or from the capacitor.
- The present invention utilizes the fact that the energy stored in or released from the capacitor depends on the absolute value of the difference between the controlled voltage V2 on the dc link and the initial voltage V1. The voltage V on the dc link is dynamically controlled so that a larger amount of energy will be stored in or released from the capacitor than it is when the voltage is not controlled. When energy is supplied from a power supply to a load, energy from the power supply as well as energy stored in the capacitor is supplied to the load. Moreover, when energy is recovered from the load, energy is recovered not only into the power supply but also into the capacitor. This facilitates energy supply and energy recovery. Consequently, supply of energy from the power supply or recovery of energy into the power supply is effectively minimized.
- For example, in a numerically controlled machine tool, dynamic control of a dc link voltage is, similarly to control of acceleration or deceleration of a motor, performed in response to a command programmed in a numerical controller.
- A description will be made of a case where a motor is accelerated or decelerated. When the motor is accelerated or decelerated, energy is transferred between the power supply and motor via the capacitor on the dc link.
- As expressed by the formula (1), the larger the absolute value |V2−V1| of the difference between the controlled voltage V2 on the dc link and the initial voltage V1 is, the smaller an amount of energy transferred to or from the power supply is.
- To begin with, control of a dc link voltage extended for acceleration of the motor will be described in conjunction with
FIG. 3 . - For acceleration of the motor, before the motor is accelerated, the largest possible amount of energy is stored in the capacitor on the dc link. Thus, power to be supplied from the power supply is reduced and the capacity of the power supply is diminished.
- Referring to
FIG. 3 , the voltage on the dc link is elevated (b) from the initial voltage (a) on the dc link to the controlled voltage V2 on the dc link (c). With the voltage on the dc link elevated, supply of energy to the motor is started in order to start accelerating the motor (at a motor acceleration start time instant A in the drawing). When the motor is accelerated, the voltage on the dc link falls (d) and eventually reaches a constant voltage (e). - When the do voltage is elevated before acceleration of the motor is started, energy derived from a potential difference ΔV between the voltage c and voltage e can be supplied from the capacitor to the motor. The potential difference ΔV is larger than it is when the dc voltage is not elevated. Accordingly, a larger amount of energy is stored in the capacitor and a larger amount of energy is supplied to the motor.
- Next, control of a dc link voltage extended for deceleration of the motor will be described in conjunction with
FIG. 4 . - For deceleration of the motor, the largest possible amount of energy is regenerated by the motor and recovered into the capacitor. Thus, an amount of power to be supplied to the power supply is reduced, and the capacity of the power supply is diminished.
- Referring to
FIG. 4 , the voltage on the dc link is lowered (g) from an initial voltage (f) to a voltage (h) corresponding to the controlled voltage V2 on the dc link. After the voltage on the dc link is lowered, deceleration of the motor is started and recovery of regenerated energy from the motor is started (at a motor deceleration start time instant B in the drawing). As the motor is decelerated, the voltage on the do link rises (i) owing to recovered energy. Eventually, the dc voltage reaches a voltage (j). - When the dc voltage is lowered before deceleration of the motor is started, energy derived from the potential difference ΔV between the voltage h and voltage j is recovered into the capacitor. The potential difference ΔV is larger than it is when the dc voltage is not lowered. Accordingly, a larger amount of energy is recovered into the capacitor, and a larger amount of energy is recovered from the motor. Consequently, an amount of energy recovered by the power supply or a resistor is decreased. Recovery by the power supply causes a loss in energy over a power line because a current is regenerated. Energy recovered by the resistor is consumed as thermal energy. According to the present invention, the energy loss is decreased by reducing recovery by the power supply or by the resistor.
-
FIG. 5 shows the relationship between a programmed command and changes in a dc link voltage and a motor speed. Referring toFIG. 5 ,reference numeral 20 denotes the motor speed, andreference numeral 22 denotes the dc link voltage. Acommand 26 for elevating the dc link voltage is written in a program before to amotor acceleration command 24. The command for elevating the dc link voltage is released at a step at which the motor is accelerated to a predetermined speed (28). - Moreover, a
command 32 for lowering the do link voltage is written in the program before to amotor deceleration command 30. The command for lowering the dc link voltage is released at a step at which the motor is decelerated to a predetermined speed (for example, a zero speed) (33). - When the dc link voltage is changed, an excess input current may flow during charge or discharge of the dc link because the potential difference between a supply voltage and the dc link voltage increases.
- In order to confine the input current to a predetermined current such as a rated current of equipment, a voltage variation such as an elevation voltage difference or a lowering voltage difference and/or a length of the elevation or lowering period is specified as a parameter in a program.
-
FIG. 6A andFIG. 6B are graphs for explaining the relationship between a voltage variation |V2−V1| and a time interval T established when the link voltage is elevated (FIG. 6A ) or lowered (FIG. 62 ). - A change ΔQ in charge stored in the capacitor and a change ΔV in the voltage at the capacitor have the following relationship:
ΔQ=CΔV
where C denotes an electrostatic capacitance of the capacitor. Supposing an input current I is held constant, the following relationship is established:
ΔQ=IT
Consequently, the following formula is true:
I=C×ΔV/T
Therefore, the input current I is determined by the voltage variation ΔV (|V2−V1|) and the time interval T. If the voltage variation ΔV and time interval T are determined appropriately, the input current I can be confined to the rated current. - Moreover, either of the voltage variation ΔV and the time interval T, for example, the voltage variation ΔV (|V2−V1|) may be held constant as shown in
FIG. 6A andFIG. 6B , and the time interval T may be specified as a parameter according to a permissible current. Referring toFIG. 6A andFIG. 6B , a time interval T1 is specified for a relatively large permissible current, and a time interval T2 is specified for a relatively small permissible current. - A converter in accordance with the present invention and an inverter including the converter can be adapted to a motor in which supply and recovery of power is carried out. Moreover, the converter and inverter can be adapted to a motor in which recovery of energy is not carried out but only consumption of energy is carried out.
Claims (12)
1. A converter comprising:
a converter circuit converting an alternating current into a direct current; and
a control circuit controlling the converter circuit, said control circuit controlling a voltage of the direct current toward a higher voltage in response to an externally-issued dc voltage elevating command and/or controlling the voltage toward a lower voltage in response to an externally-issued dc voltage lowering command.
2. The converter according to claim 1 , wherein the dc voltage elevating command is externally issued when a load connected to the converter circuit via an inverter circuit that inverts a direct current into an alternating current is to be increased, and the dc voltage lowering command is externally issued when the load is to be decreased.
3. The converter according to claim 2 , wherein the load includes a motor, the increase in the load includes acceleration of the motor and the decrease in the load includes deceleration of the motor.
4. The converter according to claim 3 , wherein the dc voltage elevating command is externally issued prior to a motor acceleration command, and the dc voltage lowering command is externally issued prior to a motor deceleration command.
5. The converter according to claim 1 , wherein at least one of a voltage difference by which the dc voltage is controlled to rise and a length of a rising period is externally designated.
6. The converter according to claim 1 , wherein at least one of a voltage difference by which the dc voltage is controlled to fall and a length of a falling period is externally designated.
7. An inverter comprising:
a converter circuit converting an alternating current into a direct current;
an inverter circuit, connected to the converter circuit, inverting a direct current fed from the converter circuit into an alternating current; and
a control circuit controlling the converter circuit and inverter circuit, said control circuit controlling a voltage of the direct current toward a higher voltage in response to an externally-issued dc voltage elevating command and/or controlling the voltage toward a lower voltage in response to an externally-issued dc voltage lowering command.
8. The inverter according to claim 7 , wherein the dc voltage elevating command is externally issued when a load connected to the inverter circuit is to be increased, and the dc voltage lowering command is externally issued when the load is to be decreased.
9. The inverter according to claim 8 , wherein the load includes a motor, the increase in the load includes acceleration of the motor, and the decrease in the load includes deceleration of the motor.
10. The inverter according to claim 9 , wherein the do voltage elevating command is externally issued prior to a motor acceleration command, and the dc voltage lowering command is externally issued prior to a motor deceleration command.
11. The inverter according to claim 7 , wherein at least one of a voltage difference by which the dc voltage is controlled to rise and a length of a rising period is externally designated.
12. The inverter according to claim 7 , wherein at least one of a voltage difference by which the dc voltage is controlled to fall and a time interval length of a falling period is externally designated.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2004007226A JP3974899B2 (en) | 2004-01-14 | 2004-01-14 | Converter device and inverter device provided with converter device |
JP2004-007226 | 2004-01-14 |
Publications (1)
Publication Number | Publication Date |
---|---|
US20050151503A1 true US20050151503A1 (en) | 2005-07-14 |
Family
ID=34616872
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/034,719 Abandoned US20050151503A1 (en) | 2004-01-14 | 2005-01-14 | Converter and inverter including converter circuit |
Country Status (4)
Country | Link |
---|---|
US (1) | US20050151503A1 (en) |
EP (1) | EP1555744A3 (en) |
JP (1) | JP3974899B2 (en) |
CN (1) | CN1641989A (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20090009126A1 (en) * | 2007-07-02 | 2009-01-08 | Fanuc Ltd | Numerical controller controlling acceleration and deceleration of respective control axes up to command speeds |
US20100102762A1 (en) * | 2007-10-23 | 2010-04-29 | Mitsubishi Heavy Industries, Ltd. | Power converter |
US20100207598A1 (en) * | 2007-07-26 | 2010-08-19 | Toyota Jidosha Kabushiki Kaisha | Voltage conversion device |
US20120275202A1 (en) * | 2011-04-26 | 2012-11-01 | Kabushiki Kaisha Yaskawa Denki | Series multiplex power conversion apparatus |
US20140035507A1 (en) * | 2012-07-31 | 2014-02-06 | Delta Electronics, Inc. | Motor deceleration method and motor driving apparatus applying the motor deceleration method |
US20220014117A1 (en) * | 2012-09-13 | 2022-01-13 | Moog Inc. | Active voltage bus system and method |
DE102021211817A1 (en) | 2021-10-20 | 2023-04-20 | Robert Bosch Gesellschaft mit beschränkter Haftung | Method for controlling an intermediate circuit voltage on an intermediate circuit capacitor of a drive machine |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7310254B2 (en) * | 2006-02-15 | 2007-12-18 | Rockwell Automation Technologies, Inc. | AC-to-AC (frequency) converter with three switches per leg |
JP4867619B2 (en) * | 2006-07-10 | 2012-02-01 | パナソニック株式会社 | Power supply |
JP5319318B2 (en) | 2009-02-02 | 2013-10-16 | アイダエンジニアリング株式会社 | Motor drive control device |
DE102009008048A1 (en) * | 2009-02-09 | 2010-08-19 | Siemens Aktiengesellschaft | Method for controlling a self-commutated mains converter of a voltage source inverter |
JP5653428B2 (en) * | 2010-06-23 | 2015-01-14 | 住友重機械工業株式会社 | Injection molding machine and power regeneration converter |
JP4917680B1 (en) | 2010-09-16 | 2012-04-18 | ファナック株式会社 | Motor drive device using a capacitor |
JP5527127B2 (en) * | 2010-09-16 | 2014-06-18 | 株式会社デンソーウェーブ | Robot system |
AT512995A1 (en) * | 2012-05-18 | 2013-12-15 | Fronius Int Gmbh | Method for controlling a current source, as well as current source and process controller therefor |
JP6364307B2 (en) * | 2014-10-14 | 2018-07-25 | 株式会社日立情報通信エンジニアリング | Power supply device and uninterruptible power supply system using the same |
JP6438453B2 (en) * | 2016-12-21 | 2018-12-12 | ファナック株式会社 | Motor drive device |
JP7342595B2 (en) * | 2019-10-10 | 2023-09-12 | オムロン株式会社 | power converter |
CN114188933B (en) * | 2021-12-09 | 2023-06-02 | 南方电网电力科技股份有限公司 | Direct current collecting system of wave energy power generation device and control method and system thereof |
Citations (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4329099A (en) * | 1977-02-23 | 1982-05-11 | Kabushiki Kaisha Yamashina Seikosho | Self-drilling and self-extruding fastener |
US4375612A (en) * | 1979-09-12 | 1983-03-01 | Borg-Warner Corporation | Controlled regenerative d-c power supply |
US4443747A (en) * | 1982-04-01 | 1984-04-17 | General Electric Company | Transitioning between multiple modes of inverter control in a load commutated inverter motor drive |
US4511835A (en) * | 1982-12-23 | 1985-04-16 | Borg-Warner Corporation | Voltage-controlled, inverter-motor system |
US4545002A (en) * | 1983-06-28 | 1985-10-01 | General Electric Company | Thyristor voltage limiter for current source inverter |
US4697131A (en) * | 1985-12-11 | 1987-09-29 | Westinghouse Electric Corp. | Voltage source inverter and variable frequency, constant voltage AC motor drive embodying the same |
US4879639A (en) * | 1987-05-11 | 1989-11-07 | Fuji Electric Co., Ltd. | Power converter for driving an AC motor at a variable speed |
US4891744A (en) * | 1987-11-20 | 1990-01-02 | Mitsubishi Denki Kaubshiki Kaisha | Power converter control circuit |
US5663627A (en) * | 1994-07-26 | 1997-09-02 | Fujitsu General Limited | Control apparatus for controlling motor of air conditioner |
US5742493A (en) * | 1995-09-08 | 1998-04-21 | Hitachi, Ltd. | Power conversion apparatus |
US5808880A (en) * | 1996-08-30 | 1998-09-15 | Otis Elevator Company | Power factor controller for active converter |
US20010001227A1 (en) * | 1998-04-02 | 2001-05-17 | Yasuo Notohara | Motor controller |
US20020085398A1 (en) * | 2001-01-02 | 2002-07-04 | Bixel Paul S. | System and method for regenerative PWM AC power conversion |
US6732838B1 (en) * | 1999-11-17 | 2004-05-11 | Fujitec Co., Ltd. | Power supply for ac elevator |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2001037236A (en) * | 1999-07-19 | 2001-02-09 | Mitsubishi Electric Corp | Voltage control apparatus of power converting apparatus |
JP2003102177A (en) * | 2002-09-17 | 2003-04-04 | Hitachi Ltd | Method of controlling power converter |
-
2004
- 2004-01-14 JP JP2004007226A patent/JP3974899B2/en not_active Expired - Lifetime
-
2005
- 2005-01-12 EP EP05000502A patent/EP1555744A3/en not_active Withdrawn
- 2005-01-14 CN CNA2005100021761A patent/CN1641989A/en active Pending
- 2005-01-14 US US11/034,719 patent/US20050151503A1/en not_active Abandoned
Patent Citations (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4329099A (en) * | 1977-02-23 | 1982-05-11 | Kabushiki Kaisha Yamashina Seikosho | Self-drilling and self-extruding fastener |
US4375612A (en) * | 1979-09-12 | 1983-03-01 | Borg-Warner Corporation | Controlled regenerative d-c power supply |
US4443747A (en) * | 1982-04-01 | 1984-04-17 | General Electric Company | Transitioning between multiple modes of inverter control in a load commutated inverter motor drive |
US4511835A (en) * | 1982-12-23 | 1985-04-16 | Borg-Warner Corporation | Voltage-controlled, inverter-motor system |
US4545002A (en) * | 1983-06-28 | 1985-10-01 | General Electric Company | Thyristor voltage limiter for current source inverter |
US4697131A (en) * | 1985-12-11 | 1987-09-29 | Westinghouse Electric Corp. | Voltage source inverter and variable frequency, constant voltage AC motor drive embodying the same |
US4879639A (en) * | 1987-05-11 | 1989-11-07 | Fuji Electric Co., Ltd. | Power converter for driving an AC motor at a variable speed |
US4891744A (en) * | 1987-11-20 | 1990-01-02 | Mitsubishi Denki Kaubshiki Kaisha | Power converter control circuit |
US5663627A (en) * | 1994-07-26 | 1997-09-02 | Fujitsu General Limited | Control apparatus for controlling motor of air conditioner |
US5742493A (en) * | 1995-09-08 | 1998-04-21 | Hitachi, Ltd. | Power conversion apparatus |
US5808880A (en) * | 1996-08-30 | 1998-09-15 | Otis Elevator Company | Power factor controller for active converter |
US20010001227A1 (en) * | 1998-04-02 | 2001-05-17 | Yasuo Notohara | Motor controller |
US6732838B1 (en) * | 1999-11-17 | 2004-05-11 | Fujitec Co., Ltd. | Power supply for ac elevator |
US20020085398A1 (en) * | 2001-01-02 | 2002-07-04 | Bixel Paul S. | System and method for regenerative PWM AC power conversion |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20090009126A1 (en) * | 2007-07-02 | 2009-01-08 | Fanuc Ltd | Numerical controller controlling acceleration and deceleration of respective control axes up to command speeds |
US7915851B2 (en) * | 2007-07-02 | 2011-03-29 | Fanuc Ltd | Numerical controller controlling acceleration and deceleration of respective control axes up to command speeds |
US20100207598A1 (en) * | 2007-07-26 | 2010-08-19 | Toyota Jidosha Kabushiki Kaisha | Voltage conversion device |
US8644045B2 (en) | 2007-07-26 | 2014-02-04 | Toyota Jidosha Kabushiki Kaisha | Temperature controlled voltage conversion device |
US20100102762A1 (en) * | 2007-10-23 | 2010-04-29 | Mitsubishi Heavy Industries, Ltd. | Power converter |
US20120275202A1 (en) * | 2011-04-26 | 2012-11-01 | Kabushiki Kaisha Yaskawa Denki | Series multiplex power conversion apparatus |
US20140035507A1 (en) * | 2012-07-31 | 2014-02-06 | Delta Electronics, Inc. | Motor deceleration method and motor driving apparatus applying the motor deceleration method |
US20220014117A1 (en) * | 2012-09-13 | 2022-01-13 | Moog Inc. | Active voltage bus system and method |
DE102021211817A1 (en) | 2021-10-20 | 2023-04-20 | Robert Bosch Gesellschaft mit beschränkter Haftung | Method for controlling an intermediate circuit voltage on an intermediate circuit capacitor of a drive machine |
WO2023066837A1 (en) | 2021-10-20 | 2023-04-27 | Robert Bosch Gmbh | Method for controlling an intermediate circuit voltage at an intermediate circuit capacitor of a drive machine |
Also Published As
Publication number | Publication date |
---|---|
EP1555744A2 (en) | 2005-07-20 |
JP3974899B2 (en) | 2007-09-12 |
EP1555744A3 (en) | 2007-06-20 |
JP2005204391A (en) | 2005-07-28 |
CN1641989A (en) | 2005-07-20 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20050151503A1 (en) | Converter and inverter including converter circuit | |
JP4390843B2 (en) | Motor drive device | |
US8415906B2 (en) | Motor driving apparatus | |
EP1484831B1 (en) | Motor driving apparatus | |
JP5602890B2 (en) | Motor control device having power storage device and resistance discharge device | |
JP3722810B2 (en) | Motor drive device | |
US7135835B2 (en) | Converter apparatus, inverter apparatus, and DC link voltage control method | |
CN100433540C (en) | AC motor control method and control device | |
JP5997302B2 (en) | Motor drive device using a capacitor | |
KR101861889B1 (en) | Method for voltage dip compensation of inverter | |
US20120068637A1 (en) | Motor driving apparatus | |
JP6426775B2 (en) | Motor drive | |
CN109428533B (en) | Motor drive device for controlling boost ratio of PWM converter | |
CN110086379B (en) | Motor drive system having electricity storage device | |
JP3318252B2 (en) | Elevator control device | |
CN104868798A (en) | Motor Deceleration Method And Motor Driving System Using The Same | |
JP4402409B2 (en) | Elevator control device | |
CN102801383B (en) | Alternating current motor driving device with charging function and charging method thereof | |
CN202586862U (en) | Alternating current motor drive device with charging function | |
JP2005102410A (en) | Control unit of elevator | |
KR19990010127A (en) | Speed tracking method of inverter system | |
JP2023152073A (en) | servo driver | |
JP5313493B2 (en) | Motor drive device | |
JP2014003741A (en) | Common power supply device for inverter |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: FANUC LTD., JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:YAESHIMA, MAMORU;HANYU, SHIGEKI;KAGAMA, HIDEKI;AND OTHERS;REEL/FRAME:016176/0284 Effective date: 20050104 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |